[SR-Users] RTPEngine + Kamailio state question

Richard Fuchs rfuchs at sipwise.com
Thu Sep 30 19:46:01 CEST 2021

On 30/09/2021 13.34, [ EXT ] Alex Balashov wrote:
> On Sep 30, 2021, at 1:32 PM, Richard Fuchs <rfuchs at sipwise.com> wrote:
>> On 30/09/2021 13.17, [ EXT ] Alex Balashov wrote:
>>> I’m not sure how the mapping works internally. But whatever the operation is, is that value stored somewhere or possible to store somewhere so as to persist across restarts in a turn-key way?
>> AFAICR the node is selected based on a deterministic hash over the call ID. So as long as the config doesn't change between restarts, the node selected from any particular call ID would remain the same.
>> The exception is cases where the selected node was not available and the call then had to go to a secondary fallback node. AFAIK this association is stored in memory only and would be lost after a restart (which would become a problem if the previously unavailable node is now back up).
> Thanks for that. That accounts for how a Call-ID is mapped to a node within a set. But what if the set ID chosen for a particular call is nonstandard, i.e. expressly overridden with set_rtpengine_set()? Is that knowledge somehow available after a restart?
No there's no persistent state at all. I would suggest to always 
explicitly select the appropriate set before every invocation of any 
function (or at least once at the beginning of the script) regardless of 
the use case.


More information about the sr-users mailing list